The investigation into Michael Jackson's death has been completed.

The late pop legend – who died of acute Propofol intoxication in June 2009 – was last seen alive by his personal physician Dr. Conrad Murray, who is now likely to be criminally charged with Michael's death in the next couple of weeks.

Detectives working on Michael's death completed their investigation last month and the case will now be formally presented to the Los Angeles County District Attorney.

A source told gossip website TMZ the investigation was "exhaustive" and 'extremely thorough' and there was enough evidence for a criminal case against Dr. Murray.

The case is particularly complicated because the doctor did not break any laws by administering Propofol to the 'Thriller' singer but he could be charged with involuntary manslaughter, relating to gross negligence.

Dr. Murray – who did not have any criminal charges brought against him immediately after Jackson's passing - has since returned to the Armstrong Medical Clinic in Houston, Texas, where he has been treating patients.